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Abstract. The objective of this study is to isolate sulphate reduction bacteria (SRB) from acid mire water collected at Sg Pelepah Kota Tinggi, Johor Malaysia. The isolation process was conducted in high alkaline and anaerobic conditions to sustain the bacteria in concrete environment. Properties tests such as compressive strength and water penetration were conducted. The result showed that optimal growth condition of sulphate reduction bacteria is pH 9-10. It was also observed that the bacteria is a coccus shape after gram staining process. The bacteria was used after 10 days of culturing prior to growth curve measurement. The liquid culture containing sulphate reduction bacteria were used at 1%, 3% and 5% as replacement ratio of water content. Concrete specimens were cured in the air conditions for 7, 14 and 28 days. Maximum increment on compressive strength was 13.0% and decrement in water penetration was 8.5% occurred with 5% of SRB. The enhancement in compressive strength and water penetration performance was due to calcium precipitation within concrete pores. Image of scanning electronic microscopy (SEM) showed bacteria sustained and survived in concrete environment by reducing diameter of pores in concrete specimens.

In construction industry, sustainability is no longer an option but an imperative. It turns to be an essential element for project stakeholders. Although green procurement is an environmental policy instrument that considers the impact of procurement and purchasing process for the sustainability of project development. However, the concept in Malaysia is still in its early stages and encounters barriers to make a paradigm shift towards a greener approach. This paper tends to shed light on the key success factors and to develop a roadmap for implementing green procurement in building and infrastructure projects. This could pave the road for establishing a transformation plan that could gradually overcome the current challenges. In this study, 380 Malaysian corporations were surveyed to determine their perspective on 50 factors affecting procurement delivery. A number of 142 questionnaires were assessed as valid responses. Results revealed that there is an excellent consistency in the investigated factors which have been statistically analyzed. The significant factors can be categorized into themes namely, perception, organizational management, regulative, logistical, contractual, technical, strategic and financial factors.